Conventionally, a seat using a fibrous structure composed of polyester fibers or the like as a cushion body has been known (for example, see Patent Document 1, 2 cited below). The fibrous structure used in the seat described in Patent Document 1 is formed by successively folding a web obtained by dispersing and incorporating thermally adhesive composite short fibers as an adhesive component into matrix fibers composed of an inelastic polyester crimped short fiber assembly in a standing state along its longitudinal direction. That is, this fibrous structure is formed to have a predetermined thickness by folding the web in an accordion shape.
In the seat described in Patent Document 1, each of a seat portion and a seat back portion is constituted by stacking a plurality of this fibrous structures to form a cushion body and coating this cushion body with a cover. Accordingly, in this seat, since the standing direction of the web (a thickness direction of the cushion body) is directed along a load direction during sitting of a seat occupant, excellent ventilation is, of course, secured, a proper hardness to a load direction is provided, and load can be dispersed. Therefore, this seat can provide a soft touch feeling which cannot be obtained by urethane conventionally used in general.
In Patent Document 2, a plurality of fibrous structures are disposed in a stacked and compressed state in a mold having a large number of ventilation holes, and hot air and steam are ventilated through the mold. Thereby, the hot air and steam pass through the mold and the fibrous structures are thermally molded so that a cushion body with a predetermined shape is formed.
Patent Document 1: Japanese Patent Laid Open Publication No. 1996(H08)-318066. Patent Document 2: Japanese Patent Laid Open Publication No. 2000-107470.